Musk’s sun-fed battery closer to reality

IT IS a nice dream. You catch the sun’s rays in photovoltaic panels on the roof. The resulting electricity is fed down to a large battery hanging on the wall in the garage. You plug your electric car in overnight and charge it for the next day’s commute.

This is the postcarbon future, as imagined by electric car and space entrepreneur Elon Musk. Last week he tried to hasten it into existence, with a proposal by his battery and electric car maker Tesla Motors to buy solar power company SolarCity, of which he is also chairman.

There is a question of whether it makes sense to combine all these things in one company. Wall Street certainly is not convinced. But the timing of this proposed deal still highlights how close these sustainable energy technologies are to reaching the mass market. Musk is probably getting ahead of himself, but his vision is not far-fetched — provided the US government does not withdraw support for sustainable energy technologies too soon.

The technologies behind Musk’s dream have made progress for years. Batteries and solar panels do not benefit from Moore’s Law, which has brought a doubling of efficiency in semiconductors every 18 months or so. Instead, there has been a more gradual fall in the cost curve of both technologies, that brings improvements of about 5%-7% a year.

Periodic hopes for technology breakthroughs have been disappointed. After the 2008 financial crisis, for instance, the Obama administration pumped billions of dollars of stimulus money into trying to create an advanced battery industry in the US. The resulting companies were more like chemistry experiments. They might have come up with demonstrations in the lab but could not scale up in production. That has left slower-advancing lithium-ion as the default technology, particularly where lightweight batteries are needed in things like consumer electronics and transport.

Solar power has been through much the same cycle. The prospect of a step-change reduction in the cost per watt of electricity generated was one of the hopes that fed Silicon Valley’s “greentech” boom a decade ago. Boom turned to bust, and the new thin-film solar technologies turned out to be no match for the prevailing technology of the day, crystalline silicon. Instead, Chinese manufacturers brought prices down through huge investment in large-scale production. This may not have been good for the balance of trade but has helped make solar power affordable to many homeowners.

To take the next step, Musk thinks he can go one better in both batteries and solar power with what are largely incremental advances.

Silevo, a panel maker bought by SolarCity, produces hybrid products that layer some thin-film elements into crystalline silicon panels. The company will end up manufacturing panels producing “tens of gigawatthours a year” of power, according to Musk — quite an ambition considering the US is still not expected to reach even 10Gw/h this year.

In batteries, Tesla is getting close to completing a large factory in Nevada that will double the world’s production of lithium-ion cells using technology from Panasonic.

The plan is the same in both cases: find even a small edge in the mass technology of the day, scale up fast and ride the cost curve down towards world domination. But whether this formula will be enough to usher in a sustainable energy economy is in the hands of governments. Subsidies are still needed, whether of the direct or indirect sort. Musk has shown himself an astute user of government support: Silevo has been promised $225m of state backing to build a plant in New York, while Tesla itself was a beneficiary of an energy department loan guarantee.

Silevo’s advanced panels, made in China, are blocked by US antidumping laws. The firm is appealing against that exclusion, though domestic manufacturing could eventually get around the problem.

The sunshine-to-electric car dream is not far-fetched.

However, it still needs some timely assistance to become a reality. © Financial Times 2016